Apparatus for burning fuel oil



LSQLSM M. SKLOVSKY APPARATUS FOR BURNING FUEL OIL 3 sheets sheet 1 Filed March 19. 1920 July 6 1926.

M. SKLOVSKY APPARATUS FOR BURNING FUEL .OIL

Filed March 19. 1920 3 Sheets-Sheet 2 Qumran/3r; mil

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July 6 1926.,

M. SKLOVSKY APPARATUS FOR BURNING FUEL OIL:

Filed March 19. 1920 3 Sheets-Sheet 5 Patented July 6, 1926.

UNITED STATES PATENT OFFICE.

MAX SKLOVSKY, OF MOLINE, ILLINOIS, ASSIGNOR TO DEERE do COMPANY, OF LIOLINE, ILLINOIS, A CORPORATION OF ILLINOIS.

APPARATUS FOR BURNING FUEL OIL.

Application filed March 19, 1920. Serial No. 387,152.

My invention has to do with heating metallurgical furnaces to the requisite high temperature by the use of fuel oil or other equivalent fuel, and has for its object to 8 provide an improved apparatus by which the desired high temperature may not only be obtained, but may also be maintained without material variation, and by which also the temperature may be accurately regulated and the furnace be economically operated both as regards fuel consumption and care of an attendant. I accomplish this object as illustrated in the drawings and as hereinafter described. What I regard as new is set forth in the claims.

In the accompanying drawings which illustrate the preferred embodiment of my invention,

Fig. 1 is a lon itudinal vertical section of a metallurgical urnace, the air heater and fuel pipes being shown in elevation, and some parts also being broken away;

Fig. 2 is a horizontal section on line 2 2 of Fig. 3;

Fig. 3 is a vertical cross-section on line 33 of Fig. 1; i

Fig. 4 is an enlarged detail, being a partial vertical section of a fuel nozzle;

Fig. 5 is a plan view of the air heater, showing in section the pipe which supplies the same; and

Fig. 6 is a side elevation showing the air pipes connected with the heater, which is shown principally in section.

Referring to the drawings,

7 indicates a combustion chamber which may be of any suitable shape, but is preferably a square compartment having enclosing walls of fire brick. In one of the end walls, 8, is an opening 9 through which the materials to be heated may be introduced, said opening being adapted to be closed by a door 10 of any suitable description. In the construction illustrated said door is adapted to slide vertically in guides 11 at opposite sides of the door opening, as shown in Fig. 2, and is operated by a lever 12 fulcrumed at 13 upon a standard 14 mounted on the upper wall or roof 15 of the combustion chamber, as best shown in Fig. 1. The lever 12 is connected to the door 10 by a link 16 and is provided with a counterbalance 17 fo-rrelieving the operator to a greater or less extent of the weight of thedoor.

18 indicates an air supply pipe which is connected with a fan or other means of supplying air under pressure. Said pi e is connected to a tubular connection 19 w hich forms a part of an air heater 20 mounted upon the upper wall 15 of the furnace over an opening 21 placed adjacent to the lefthand end of the furnace as viewed in Fig. 1, which is the end at which the fuel is introduced, as will be hereinafter explained. The construction of the air heater 20 is best shown in Figs. 5 and 6, from an inspection of which it will be seen that said heater is a casting having a series of vertical passages 22 therethrough which when the heater is in position overlie the paxa e 21 so that waste gases passing out of combustion chamber 7 are discharg through the passages 22. The interior of the heater 20 around the passages 22 is divided intermediately b a horizontal partltion 23 into upper an lower ducts 2425 which are connected at the side farthest from the connection 19 by a vertical duct 26, as shown in Fig. 6. The lower duct 25 communicates with a circular connection 27 which is adjacent to and preferably in alinement with the connection 19, as shown in Figs. 1, 5 and 6. The arrangement of the ducts 24.-25 is such that air entering the duct 24 through connection 19 is distributed through the upper portion of the heater until it passes to the vertical duct 26 when it is in like manner caused to travel through the lower duct 25 to the connection 27 from which it is discharged into a hot air pipe 28, as best shown in Fig. 6. Thus the waste gases, which are at a high temperature, in escaping through the openings or passages 22 raise theheater20 to a high 06 temperature, and consequently highly heat the air flowing through it. The arra ement of the connections 19 and 27 provi es a convenient way of connecting them to the pipes 18 and 28, permitting the heater to be cast as an integral device.

The hot air pipe 28 leads to a. nozzle 29 fitted in a suitable opening in the end wall 30 of the furnace, as shown in Fig. 1, so that hot air may be discharged through it into the combustion chamber. The nozzle 29 is preferably what is known as a Venturi. nozzle, designed for accomplishing the intimate admixture of fuel oil in the form of a fine mist with the air flowing through the nozzle. The construction of this nozzle is best shown in Fig. 4. As' therein shown, it comprises a member 31, which in this case is an elbow, and a flaring or bell-shaped mouth 32, forming a tapered passageway 33, the smallest diameter of which is at a oint between the elbow 31 and the mouth 32. 'ear the latter point the nozzle is provided with an external circumferential channel 34, the upper portion of which communicates with the passage 33 through a minute duct 35, while the lower portion of said channel connects with an oil supply pipe 36. At a point above the duct 35 a screw lug 37 is provided so that the duct 35 may cleaned out when necessary. The arrangement is such that by causing air to flowthrough the nozzle at high velocity oil will be drawn through the duct 35 into the stream of air and will be sheared off and broken up into a fine mist by the velocity of the air. As an alternative, the oil may be introduced by forcing it through the duct 35 by pressure.

In order that the oil feed may be inspected from time to time, I provide the nozzle 29 with a peep hole 38 placed at the turn of the elbow 31 in line with the longitudinal axis of the delivery end of the nozzle, as shown in Fig. 4, and fit over said peep hole a short tube 39 having a mica window 40. Thus by looking through said window the observer may watch the delivery of fuel oil to the nozzle and observe the condition of the mixture as discharged through the mouth 32. The window 40 is removably secured in place by a screw cap 41 so that it may readily be removed or replaced when necessary;

As shown in Figs. 1 and 2 the mouth 32 of the nozzle 29 extends through the wall 30 of the furnace, and the mixture of air and finel divided oil is discharged into the com ustion chamber longitudinall thereof at substantially the central line 0 the furnace measured at approximately the trans- .verse center thereof. Placed within the combustion chamber a short distance from the inner end of the nozzle 29 is a diaphragm 42 of suitable refractory material provided with a comparatively short passage 43 which is co-axial with the mouth 32 of the nozzle, as shown in Figs. 1 and 2. In the construction shown this diaphragm is supported upon the floor 44 of the furnace by legs 45 so that a passage46 is provided below the passage 43. Thus gases in the combustion chamber may flow around all four sides of the diaphragm and gain access to the inlet end of the passage 43 from all directions.

The diameter of the passage 43 is greater than that of the open end of the nozzle 29 so that the mixed air and fuel discharged from, said nozzle may pass freely through the passage 43 without impingin against the face of the diaphragm, as in icated in said figures.

The process which the above described apparatus is designed to practice consists in injecting a mixture of a suitable finely divided fuel, such as fuel oil, and air, either hot or-cold, at high velocity into the combustion chamber of the furnace and utilizin the momentum of the incoming stream 0 air and fuel to cause a circulation in the combustion chamber of the products of previous combustion therein, by which such products of combustion will be brought into intimate association with the incoming fuel mixture before combustion thereof is accomplished. The manner in which this operation occurs will be apparent from an inspection of Figs. 1 and 2, which illustrate the course of the gas and fuel currents. As thereshown, the incomingstream of fuel and air passes at high velocity through the passage 43 in the diaphragm 42, thereby creating a suction at the inlet end or side of said passage which draws the products of previous combustion in the combustion chamber back through the space between the end wall 30 of the furnace and the diaphragm 42 and into the passage 43 by which they are confined laterally and conse uentl are merged or intimately associated with the incoming stream of air and fuel; As these products of combustion are very hot they instantly raise the incoming fuel to a high temperature so that it is gasified and ignited. The intimate association of the highly heated gasified fuel and the accompanying air which is supplied in the proper proportion to effect substantially perfect combustion, together with the circulation of the mixture in the combustion chamber, insures the complete, perfect, and substantially instantaneous combustion of the fuel without waste so that very high temperatures can be quickly obtained.

-It will be noted that b scribed the path followe much longer than it would be if they merely crossed the furnace, and consequently they are retained longer in the combustion chamber, with consequent increasing heating effect. Furthermore, as the gases in the combustion chamber are brought back to the inlet and associated with the incoming fuel mixture, the result is much quicker ignition of said mixture and a more uniform heating effect under a large range of conditions than, so far as I am aware, is obtainable with any previous method without the use of special contrivances for circulating the gases which require close attention and care.

further advantage in the process described is that the incoming fuel stream is the process doby the gases isv more readily chedked so that the gasified fuel tends to spread out ina broader stream in place of following a linear direction. This results in a more equalized heating of the bustion'is obtainable not only with no excess of air but rather with a eficiency of air as much as from twenty-five to thirty er cent. Such process also facilitates startmg the furnace, as on account of the rotative character of the flame immediately u on ignition the live flame is turned back behind the diaphragm and the mixing of the incoming fuel with the high temperature flame is almost instantaneous so that gasification is started immediately, the result being that after ignition the fuel burns as a gas with all the advantages of gaseous combustion.

In the drawings the diaphragm is shown as supported on the floor of the combustion chamber a short distance from the discharge point of the nozzle 29, but it will be understood that this is illustrative merely, as the diaphragm may be otherwise mounted, the essential feature being that it be so arranged as to permit access of the products of previous combustion to the inlet side of the passage 43. It should, however, be so placed that it does not form an obstacle in the direct path of the incoming gaseous mixture so that no substantial deteration results, owing to the absence of any direct washin action thereon of liquid fuel ar ticles 0 high velocity. While mixing 0 the incoming fuel stream and the rotative current of live gases occurs at the entrance of the passage 43 and in said passage, and while ignition is initiated while such gases are traveling through said passa e and rapid ignition takes place immediate y upon the exit of the gases from such passage, it is to be noted that deterioration of said passage does not occur and no hot spots are produced because the time required for the movement of the gases through said passage is so small (being much less than 1/100 part of a second, and usually nearer 1/1000 part of a second, due both to the high velocity of the mixture and the short length of the passage,) that there is insuflicient time for combustion to be completed within it. Furthermore, as the incoming fuel stream passes through approximately the middle of the passage 43 the current of live gases acts as an envelope that surrounds the fuel stream closely and insulates it from direct contact with the walls of the passage.

By the method described it is possible to regulate the temperature within a furnace to almost any degree desired by controlling the ratio of mixture of air and fuel, and the extent to which the air mixed with the fuel oil is preheated. Where the highest tem peratures are desired the mixture of fuel oil and air is in the roportion required for exact chemical com hination and the air is preheated to any desired extent, the limits of preheating being determined by the mater1al through which the air is conducted. Likewise low tem "ratures can be produced by the injection 0 excess air in much larger proportion than has heretofore been found 7 practicable. This is made possible by the auxiliary current introduced through the diaphragm, which insures ignition of the mixture even if the temperature is comparatively subnormal. This low temperature can also be maintained substantially uniformly throughout the combustion chamber, for the reason hereinbefore mentioned, in contrast with the localized heat obtained in a furnace by the usual practice where excess air is used to reduce the temperature and where the average temperature is obtained by localizing therein the high temperatures at that part of the combustion chamber where. combustion occurs and the localizing of cold zones where no combustion takes place. Experiments have also indicated that by my improved method it is not only possible to use the proper amount of air for exact combustion, but also that it is practicable to use a subnormal amount of air. For example, as low as 70 per cent. of the quantity of air required for exact combustion can be used without causing smoke, the combustion being largely GO, (10 and unburned gases which ignite whenthey are discharged into the atmosphere. This feature is particularly important where oxidation is to be eliminated to the utmost by the use of a smokeless deoxidizing or reducingaflame.

The apparatus described is a simple form of furnace adapted and arranged to practice the process above described, but it should be understood that the claims are not intended to be limited to the specific arrangement shown and described except in so far as they are directed specifically to details of construction.

What I claim as my invention and desire to secure by Letters Patent, is-- 1. A furnace, comprising a combustion chamber, a nozzle commumcating with one end portion thereof for an plying thereto at high velocity a mixture 0 air and a suitable hydro-carbon fuel, a diaphragm in said combustion chamber having a passage in alinement with said nozzle, said diaphragm bein set a short distance away from said nozz e, and both ends of said passage being in direct communication with the combustion chamber, and an outlet for waste gases opening into the combustion chamber.

2. A furnace comprising a combustion chamber, a nozzle for introducing fuel thereinto, a passage in alinement with said 1 nozzle, the inlet and outlet ends of said assage being open to the combustion cham r, an outlet for waste gases opening into the combustion chamber and means over said outlet for heating the air supplied to the combustion chamber.

3. An air heating device -for furnaces comprising a unitary box-like member having a plurality of air passages extendin in one direction therethrough, a partition m a plane which intersects said passages, formmg separate ducts in said member at opposite sides of said partition extending around said passages, a duct at one end portion of said member connecting said separate duct-s together, and connections at the op posite end portion of said member communicating respectively with said separate ducts 4. An air heating device for furnaces comprising an integral box-like member having a plurality of air passages extending in one direction therethrough, an integral partition in a plane which intersects said passages, forming separate ducts in said member at opposite si es of said artition extending around said passa es, a not at one end portion of said mem r connecting said separate ducts together, and connections at the opposite end portion of said member communicating respectively with said separate ducts.

5. An air heating device for furnaces comprising a box-like member having a plurality of air passages extending in one direction therethrough, a partition in a plane which intersects said passages, forming separate ducts in said member at opposite sides of said partition extending around said passages, a duct at one end portion of said member connecting said separate ducts together,

and alined connections at the opposite end portion of said member communicating respectively with said separate ducts.

MAX- SKLOVSKY. 

